System for assembling/disassembling windmills

Abstract

A system for assembling/disassembling a windmill in a supporting tower, comprising a intermediate fixing structure with hydraulic supports for attachment, by pressure, to the tower; a main structure capable of being attached to the tower at various working positions by absorbing the diametral differences of the latter; two pivoting arms hinged to the main structure and capable of being positioned by hydraulic actuators; a secondary structure for hoisting tower segments, equipped with four cranes of a minor size for handling the main structure and the pivoting arms during hoisting/descent, and a counterbalancing group adjustable in height by means of capstans. The main structure and the intermediate structure include a detachable side for their withdrawal and separation from the tower during disassembly.

The invention claimed is: 
     
       1. A system for assembling/disassembling windmills including constructive components that include a tower, a nacelle and a rotor, comprising:
 a main structure, having one hoisting point or two hoisting points at different heights, being configured to be coupled at different working positions to a tower of a windmill, which is one of under construction or constructed, as a holding pillar 
 four electrically operated cranes for hoisting or lowering the main structure in an ascent or descent operation along the tower, wherein, in hoisting or lowering the main structure, a geometry of the main structure is varied to avoid collision with the constructive components; 
 wherein the main structure is further configured as a load holding element movably attachable to a tower segment at a beginning of tower construction, at an end of the tower construction and during the ascent or descent operation between the beginning and end of the tower construction, 
 arms being coupled to the main structure to generate pressure to transmit stresses to the tower, wherein the arms have a structure that is adjustable via a hydraulic system of hydraulic actuators and hydraulic cylinders to generate working pressures against the tower to accommodate different diameters of the tower during the ascent or descent operation along the tower, wherein springs are arranged to maintain the working pressure in an event of a failure of the hydraulic system; 
 an intermediate fixing structure, which is configured for fixable attachment to another tower segment, comprises a plurality of pressure arms positionable at a handling point located below a top of the another tower segment and above a center of gravity of the another tower segment; 
 two pivoting arms coupled to the main structure having a pulley system and two hooks; 
 an auxiliary beam, having an anchor hook for connecting to the constructive component of the windmill, connectable to the two hooks of the two pivoting arms, wherein translational and rotational movement is imparted to the anchor hook to adjust and position the connected constructive component, 
 wherein, while on the ground, correct positions for tower segments are indicated before being attached to the intermediate fixing structure so the tower segments are placed, without rotation, on the tower under construction. 
 
     
     
       2. The system according to  claim 1 , wherein the main structure includes a set of two wires integrally attached to a lower part of the windmill and to capstans allowing the main structure to handle loads without transferring bending stresses to the tower. 
     
     
       3. The system according to  claim 1 , wherein each of the capstans is either anchored in the ground or is locked in position by counterweights. 
     
     
       4. The system according to  claim 1 , wherein each of the two arms is linked to the main structure by hydraulically actuated mechanical elements allowing for rotation of each arm to modify a position of the two hooks. 
     
     
       5. The system according to  claim 1 , wherein the main structure includes capstans rigidly attached to a rear portion of the main structure, so that, via the pulley system, loads are transmitted from the rear portion of the main structure to the two hooks. 
     
     
       6. The system according to the  claim 1 , wherein the intermediate fixing structure comprises a frame with a removable side and wherein for disassembling the intermediate fixing structure from the tower, the removable side is removed from the frame. 
     
     
       7. The system according to the  claim 1 , wherein the main structure comprises a frame with a removable side and wherein for disassembling the main structure from the tower, the removable side is removed from the frame. 
     
     
       8. The system according to  claim 1 , wherein the plurality of pressure arms of the intermediate fixing structure fixably attach the intermediate fixing structure to the different tower segment to reduce a crane height required for installation to a minimum. 
     
     
       9. A method of using the system according to  claim 1  to at least one of assemble or disassemble a windmill, comprising:
 sequentially moving the main structure and the intermediate fixing structure along a length of a tower, 
 whereby the main structure and the intermediate fixing structure are placed at any working position for installation, repair or maintenance of the windmill.